Let me quote her again:
"We should invade their countries, kill their leaders, and convert them to Christianity"
How can you read this to suggest something other than forced conversion? She didn't say "preach them the gospel". She said "convert them". If you see anything in her words which suggests she favors allowing them a choice, please explain it to me.
I suspect that your puzzlement stems from a lack of understanding of Islam. - Islam is not followed due to belief, it is the law in islamic countries. One follows Islam from birth because if one does not, he loses hands, feet, sex organs, or his head, depending upon the extent of his heresy, and what the Mullah had for breakfast.
To 'convert' such people to anything merely requires sufficient threat of violence, since that is the basis of their culture. - The article was Satire; get a grip.
She never said anything that suggests forbidding them the choice, either.
Physicist: I somehow don't get the impression that she's inviting them to a Promise Keeper's rally and hoping they'll see the light.
But do you really expect Coulter advocates the US Army Chaplain corps preaching to an audience of captive Taliban? The words used, "impression, suggestion.." reveal the extremely subjective nature of interpreting things. Following the Principle of Charity, I will give the benefit of the doubt to Coulter until she proves herself unworthy of such benefit. It's not as though she's in the streets chanting "Death to the infidel!" and making Xena-ululations.